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Abstract Background The health system in South Sudan faces extreme domestic resource constraints, low capacity, and protracted humanitarian crises. Supportive supervision is believed to improve the quality of health care and service delivery by compensating for flaws in health workforce management. This study aimed to explore the current supervision practices in South Sudan and identify areas for quality improvement. Methods The study employed qualitative approaches to collect and analyse data from six purposefully selected counties. Data were collected from 194 participants using semi-structured interviews (43 health managers) and focus group discussions (151 health workers). Thematic content analysis was used to yield an in-depth understanding of the supervision practices in the health sector. Results The study found that integrated supportive supervision and monitoring visits were the main approaches used for health services supervision in South Sudan. Supportive supervision focused more on health system administration and less on clinical matters. Although fragmented, supportive supervision was carried out quarterly, while monitoring visits were either conducted monthly or ad hoc. Prioritization for supportive supervision was mainly data driven. Paper-based checklists were the most commonly used supervision tools. Many supervisors had no formal training on supportive supervision and only learned on the job. The health workers received on-site verbal feedback and, most times, on-the-job training sessions through coaching and mentorship. Action plans developed during supervision were inadequately followed up due to insufficient funding. Insecurity, poor road networks, lack of competent health managers, poor coordination, and lack of adequate means of transport were some of the challenges experienced during supervision. The presumed outcomes of supportive supervision were improvements in human resource management, drug management, health data reporting, teamwork, and staff respect for one another. Conclusion Supportive supervision remains a daunting task in the South Sudan health sector due to a combination of external and health system factors. Our study findings suggest that strengthening the processes and providing inputs for supervision should be prioritized if quality improvement is to be attained. This necessitates stronger stewardship from the Ministry of Health, integration of different supervision practices, investment in the capacity of the health workforce, and health infrastructure development.

User-friendly single-photon sources with high photon-extraction efficiency are crucial building blocks for photonic quantum applications. For many of these applications, such as long-distance quantum key distribution, the use of single-mode optical fibers is mandatory, which leads to stringent requirements regarding the device design and fabrication. We report on the on-chip integration of a quantum dot (QD) microlens with a 3D-printed micro-objective in combination with a single-mode on-chip fiber coupler. The practical quantum device is realized by the deterministic fabrication of the QD-microlens via in situ electron-beam lithography and the 3D two-photon laser writing of the on-chip micro-objective and fiber chuck. A QD with a microlens is an efficient single-photon source, whose emission is collimated by the on-chip micro-objective. A second polymer microlens is located at the end facet of the single-mode fiber and ensures that the collimated light is efficiently coupled into the fiber core. For this purpose, the fiber is placed in an on-chip fiber chuck, which is precisely aligned to the QD-microlens thanks to the sub-micrometer processing accuracy of high-resolution two-photon direct laser writing. The resulting quantum device has a broadband photon extraction efficiency, a single-mode fiber-coupling efficiency of 22%, a measured single-photon flux of 42 kHz (8.9 kHz) under cw (pulsed) optical excitation, which corresponds to 1.5 MHz (0.3 MHz) at the single-mode fiber output, and a multi-photon probability in terms of g(2)(0) = 0.00±0.000.04 (0.13 ± 0.05) under cw (pulsed) optical excitation. The stable design of the developed fiber-coupled quantum device makes it highly attractive for integration into user-friendly plug-and-play quantum applications.

In the present work, we investigate the coupling of deterministically pre-selected In(Ga)As/GaAs quantum dots (QDs) to low Q circular Bragg grating cavities by employing a combination of state-of-the-art low-temperature in-situ optical lithography and electron-beam lithography. The spatial overlap between the cavity mode and quantum emitter is ensured through the accurate determination of the QD position via precise interferometric position readout. Simultaneously, the high precision of the electron-beam lithography is exploited for the cavity fabrication. In order to optimize the spectral overlap, prior to cavity fabrication, finite-difference time-domain simulations are performed to estimate the spectral position of the cavity mode. A Purcell factor of 2 together with an increased count rate is reported for a deterministically positioned cavity where the emission line is detuned by 3.9 nm with respect to the cavity mode. This non-negligible Purcell enhancement for large detunings and, thus, the large range where this can be achieved points towards the possibility of using the cavity for the simultaneous enhancement of spectrally distinct transitions from the same quantum emitter located spatially in the mode maximum. Furthermore, investigations on the bending of the cavity membrane and the effects on the cavity mode and QD emission are presented. [ABSTRACT FROM AUTHOR]

Background: The health system in South Sudan faces extreme domestic resource constraints, low capacity, and protracted humanitarian crises. Supportive supervision is believed to improve the quality of health care and service delivery by compensating for flaws in health workforce management. This study aimed to explore the current supervision practices in South Sudan and identify areas for quality improvement.Methods: The study employed qualitative approaches to collect and analyse data from six purposefully selected counties. Data were collected from 194 participants using semi-structured interviews (43 health managers) and focus group discussions (151 health workers). Thematic content analysis was used to yield an in-depth understanding of the supervision practices in the health sector.Results: The study found that integrated supportive supervision and monitoring visits were the main approaches used for health services supervision in South Sudan. Supportive supervision focused more on health system administration and less on clinical matters. Although fragmented, supportive supervision was carried out quarterly, while monitoring visits were either conducted monthly or ad hoc. Prioritization for supportive supervision was mainly data driven. Paper-based checklists were the most commonly used supervision tools. Many supervisors had no formal training on supportive supervision and only learned on the job. The health workers received on-site verbal feedback and, most times, on-the-job training sessions through coaching and mentorship. Action plans developed during supervision were inadequately followed up due to insufficient funding. Insecurity, poor road networks, lack of competent health managers, poor coordination, and lack of adequate means of transport were some of the challenges experienced during supervision. The presumed outcomes of supportive supervision were improvements in human resource management, drug management, health data reporting, teamwork, and staff respect for one another.Conclusion: Supportive supervision remains a daunting task in the South Sudan health sector due to a combination of external and health system factors. Our study findings suggest that strengthening the processes and providing inputs for supervision should be prioritized if quality improvement is to be attained. This necessitates stronger stewardship from the Ministry of Health, integration of different supervision practices, investment in the capacity of the health workforce, and health infrastructure development. [ABSTRACT FROM AUTHOR]

User-friendly single-photon sources with high photon-extraction efficiency are crucial building blocks for photonic quantum applications. For many of these applications, such as long-distance quantum key distribution, the use of single-mode optical fibers is mandatory, which leads to stringent requirements regarding the device design and fabrication. We report on the on-chip integration of a quantum dot (QD) microlens with a 3D-printed micro-objective in combination with a single-mode on-chip fiber coupler. The practical quantum device is realized by the deterministic fabrication of the QD-microlens via in situ electron-beam lithography and the 3D two-photon laser writing of the on-chip micro-objective and fiber chuck. A QD with a microlens is an efficient single-photon source, whose emission is collimated by the on-chip micro-objective. A second polymer microlens is located at the end facet of the single-mode fiber and ensures that the collimated light is efficiently coupled into the fiber core. For this purpose, the fiber is placed in an on-chip fiber chuck, which is precisely aligned to the QD-microlens thanks to the sub-micrometer processing accuracy of high-resolution two-photon direct laser writing. The resulting quantum device has a broadband photon extraction efficiency, a single-mode fiber-coupling efficiency of 22%, a measured single-photon flux of 42 kHz (8.9 kHz) under cw (pulsed) optical excitation, which corresponds to 1.5 MHz (0.3 MHz) at the single-mode fiber output, and a multi-photon probability in terms of g(2)(0) = 0.00±0.040.00 (0.13 ± 0.05) under cw (pulsed) optical excitation. The stable design of the developed fiber-coupled quantum device makes it highly attractive for integration into user-friendly plug-and-play quantum applications. [ABSTRACT FROM AUTHOR]

In the present study, we developed a deterministic fabrication process for an electrically driven single-photon light-emitting diode based on InP quantum dots (QDs) emitting in the red spectral range, where the wavelength of interest coincides with the high efficiency window of most commonly available standard Si avalanche photodiodes (APDs). A deterministic lithography technique allowed for the preselection of a suitable QD, here exclusively operated under electrical carrier injection. The final device was characterized under micro-electroluminescence in the direct current as well as in pulsed excitation mode. In particular, under pulsed excitation of one device, single-photon emission has been observed with g raw (2) (0) = 0.42 ± 0.02 , where the nonzero g(2)-value is mainly caused by background contribution in the spectrum and re-excitation processes due to the electrical pulse length. The obtained results constitute an important step forward in the fabrication of electrically driven single-photon sources, where deterministic lithography techniques can be used to sensibly improve the device performances. In principle, the developed process can be extended to any desired emitter wavelength above 600 nm up to the telecom bands. [ABSTRACT FROM AUTHOR]

In the present study, we report on the deterministic integration of quantum dots, emitting in the telecom O-band, into wet-chemically fabricated Gaussian-shaped microlenses which exhibit a surface quality comparable to epi-ready wafers. The slow wet-chemical etching rate enables us to gain control of the lens aspect-ratio and the vertical position with respect to the quantum dot, allowing us to engineer the far field shape to better match the acceptance profile of single-mode fibers. Maximum light enhancement values of around 10 to 16 could be achieved for collection numerical apertures from 0.6 to 0.2, respectively. The current results constitute an important step forward in transferring state-of-the-art performances achieved in the near-infrared regime to the key wavelengths for long distance fiber communication. [ABSTRACT FROM AUTHOR]

Urbanization and achieving sustainable agriculture are both major societal challenges. By reducing food miles and connecting people with nature, food cultivation in cities has several major advantages. However, due to further urban development (peri-) urban agriculture (UPA) is under threat. To strengthen UPA, we argue for considering UPA as a nature-based solution (NbS) supporting systemic approaches for societal challenges. However, academic knowledge on UPA’s contribution to various societal challenges of urbanization is still fragmented. This study addresses the gap by conducting a systemic literature review, incorporating 166 academic articles focusing on the global north. The results of the review show that UPA contributes to ten key societal challenges of urbanization: climate change, food security, biodiversity and ecosystem services, agricultural intensification, resource efficiency, urban renewal and regeneration, land management, public health, social cohesion, and economic growth. The value of UPA is its multifunctionality in providing social, economic and environmental co-benefits and ecosystem services. When implementing UPA, social, institutional, economic, technical, geographical, and ecological drivers and constraints need to be considered. To upscale UPA successfully, the study develops an integrative assessment framework for evaluating the implementation and impact efficiency of UPA. This framework should be tested based on the example of edible cities. [ABSTRACT FROM AUTHOR]

In the current study, we report on the deterministic fabrication of solid immersion lenses (SILs) on lithographically pre-selected semiconductor quantum dots (QDs). We demonstrate the combination of state-of-the-art low-temperature in-situ photolithography and femtosecond 3D direct laser writing. Several QDs are pre-selected with a localization accuracy of less than 2 nm with low-temperature lithography and three-dimensional laser writing is then used to deterministically fabricate hemispherical lenses on top of the quantum emitter with a submicrometric precision. Due to the printed lenses, the QD light extraction efficiency is enhanced by a factor of 2, the pumping laser is focused more, and the signal-to-noise ratio is increased, leading to an improved localization accuracy of the QD to well below 1 nm. Furthermore, modifications of the QD properties, i.e. strain and variation of internal quantum efficiency induced by the printed lenses, are also reported. [ABSTRACT FROM AUTHOR]